No popular entertainer has been more closely scrutinized than Bob Dylan. His garbage has been emptied, his lyrics computer-scanned, his daily wherabouts logged with an obsessive thoroughness worthy of J. Edgar Hoover's G-men. And still he is a mystery. Above all performers, Dylan showed his generation how to seize the licence they unanimously demanded: the right to express themselves. Before him, Elvis loosened the restrictions of class and race; then the Beatles and the Stones subverted the outmoded codes of domestic and public behaviour. But Dylan did more: his use of language liberated lyricists, moving them beyond Tin Pan Alley's teenagers-in-love themes, and his attitudes shaped the development of other performers who would themselves influence millions.